About 40% of the water Californians use at home is used outdoors. Large water savings can be gained by efficient landscape design, installation, management, and maintenance. This is accomplished by choosing climate adapted plants, improving soil conditions, using, and maintaining high efficiency irrigation equipment and managing the irrigation schedule to fit the plants water needs as they are influenced by local climate. To increase water efficiency and better use a valuable resource, rainwater and stormwater collection and graywater and recycled water can replace or augment potable water use in landscapes.
New development and retrofitted landscape water efficiency standards are governed by the Model Water Efficient Landscape Ordinance (MWELO). The MWELO is also referenced by Title 24, Part 11, Chapters 4 and 5 CalGreen Building Code. All local agencies must adopt, implement, and enforce the MWELO or a local Water Efficient Landscape Ordinance (WELO) that is at least as effective as the MWELO. Usually, local agencies that adopt WELOs create a more stringent ordinance than MWELO.
The purpose of water efficient landscape ordinances is to not only increase water efficiency but to improve environmental conditions in the built environment. Landscaping should be valued beyond the esthetic because landscapes replace habitat lost to development and provide many other related benefits such as improvements to public health and quality of life, climate change mitigation, energy and materials conservation and increased property values.
Local agencies are required to report on implementation annually by January 31 of each year to DWR’s Water Use Efficiency branch using the WUEdata Portal.
DWR worked with local agencies, water suppliers, landscape industry groups and public interested parties to prepare the current (2015) updated MWELO. To join a list of MWELO interested parties or to join the active Landscape Statewide Advisory Group (LSAG) email Landscape@water.ca.gov with either “MWELO interested party” or “Join LSAG” in the subject line.
Rulemaking Announcement
Regulation Rulemaking on the Model Water Efficient Landscape Ordinance (MWELO)
MWELO Public Notice
A recording of the MWELO Public Rulemaking held on January 9, 2024 is available.
New for 2020:
Beginning with 2020 MWELO reports, DWR is using the WUEdata portal for submission of Local Agency annual MWELO Implementation reports. Setting Up Your WUEdata MWELO Reporting Account
WUEdata Portal
2015 - 2019 MWELO Report Assistance and Forms:
To submit 2015-2019 MWELO Reports to DWR, please download and fill the appropriate year’s Report Template below. Send it completed in Excel format to WELO@water.ca.gov.
To view and download previous submissions, please see MWELO Implementation Reports below.
Report Templates for Previous Reporting Years:
MWELO References
